To prevent loss of aroma or flavor, coffee grounds and tea have been packaged under vacuum or inert gas in gas-impermeable containers such as cans and bags. A first problem with such package is that the user has to measure and handle the messy loose grounds. A second problem is that once the sealed container is opened, the aroma quickly escapes and the moisture and oxygen in atmosphere quickly enter the container, causing quick flavor deterioration of the remaining coffee grounds in the container.
Recently, coffee grounds has been pre-measured and then sandwiched between paper filters to form a filter pack or cartridge. About a dozen such filter packs are then packaged in one gas-impermeable can or bag to preserve the aroma and flavor of the coffee grounds in the filter packs. This improved packaging solved the above first problem, but still has the second problem. To address both the problems, coffee grounds has been first pre-measured and packaged as filter packs. Each filter pack is then immediately packaged or sealed in a gas-impermeable film pouch. About a dozen such film pouches are then packaged in a box for storage. Although such a package resolved the both the above problems, it significantly increases the cost for a cup of coffee due to its high packaging cost, and is thus not affordable by some consumers. In addition, such a package is inconvenient to use since it requires numerous steps, although each step is simple, to obtain a filter pack. Such steps includes opening the box, removing a film pouch from box, tearing the pouch to open it, pulling the filter pack out of the pouch, and closing the box. Furthermore, such a package may cause deformation to the shape of the filter packs and changes in packing density of the coffee grounds in a filter pack during transportation and handling, thus making the strength of brewed coffee inconsistent. The present invention intends to provide a new packaging method for beverage materials to resolve all above problems.